A number of gravity-operated flag or signal devices for mailboxes have been devised in the prior art. Some examples of such devices are those disclosed in U.S. Pat. Nos. 823,791 (Kitchen); 878,036 (Brown); 1,456,543 (Feist); 1,530,150 (Allan); 2,353,915 (Roe); 3,143,287 (Holt); 3,325,092 (Hoffman); 3,602,424 (Raulston) although it will be understood that this listing is not, and is not represented to be, exhaustive. The Kitchen patent discloses a mailbox signal including a flag-type indicator having a crescent-shaped cam affixed to one end thereof and disposed within the mailbox. A spring member affixed to the mailbox cover includes a V-shaped lug which engages the cam when the cover is closed so as to maintain the flag in an upright position. When the cover is lifted, the lug is disengaged and the flag falls by its own weight to an inoperative position. The Roe patent discloses a gravity-operated mailbox flag which is pivotably mounted and is slotted or notched at one end so as to engage an angle bar mounted on the mailbox door. When the mailbox is opened, the flag is released and falls to an inoperative position. The Holt patent discloses a mailbox signal device including a flag which pivots away from the mailbox when a tab thereon is released from engagement with a flange on the mailbox door by opening of the door. The Hoffman and Raulston patents disclose gravity operated, flag-type signal devices wherein the flag drops under the force of gravity to a second position thereof when a tab carried by the mailbox door is released in response to the opening of the door. The remaining patents disclose similar devices for indicating when the mailbox door or cover has been opened.
Although the devices disclosed in these patents will serve their intended function, the devices, as discussed hereinbelow, do suffer certain disadvantages as compared to the gravity operated, flag indicator device of the present invention.